Posted on by Jón Frímann

Special report: Update 3 on El Hierro eruption in Canary Islands, Spain

I am going to fully integrate Canary Islands into my watch volcano monitoring system in the beginning of next month, but Canary Island won’t be part of my emergency system until I move to Canary Island (that is because of technical reasons mostly). When that happens, blog post regarding earthquake and volcano activity won’t be a special report. Just a normal blog post as with Icelandic volcanoes. I am doing this as I plan on moving to Canary Islands in about 10 years time (+- maybe few years depending on how my plans work out). A name change on this blog is planned in the beginning of the year 2012. But it takes a while for me to think up a new name for this blog.
******

The eruption in El Hierro volcano continues at the same phase as before. With little change so far. Currently the eruption seems to be in two vents, as it did when it started on Monday. There have been unconfirmed reports of new vents opening up closer to the coastline. But given lack of direct evidence that should be there. I do not believe that a new vents have opened up closer to the coastline so far.

Deep earthquake continue in El Hierro volcano. But that means a new magma is coming in from the mantle and is flowing upwards into the volcano. For long as deep earthquakes are being recorded the eruption is going to continue. It is impossible to know for how long this inflow of magma from the mantle is going to continue. But this means that the eruption is going to continue for time being. With the risk that new vents might open up at any time on and around El Hierro volcano. This inflow of new magma has also been confirmed by GPS measurements on El Hierro volcano (the island). But since the eruption did start, no major change has been seen on the GPS real time data.


The harmonic tremor in El Hierro volcano yesterday. Copyright of this picture belongs to Instituto Geográfico Nacional.


The harmonic tremor in El Hierro volcano today (until 21:20 UTC about). As can be seen by comparing the pictures between today and yesterday. Not much has changed since yesterday in terms or harmonic tremor. Copyright of this picture belongs to Instituto Geográfico Nacional.

If a eruption vents open up on a land. The following eruption is going to be lava only. No volcano ash and no explosions as El Hierro is a shield volcano like the one on Hawaii and that means only lava eruptions. If a eruption vents opens up on the shallow coastline, there are going to be explosions for as long the ocean water can get into the crater. The moment it closes up the explosions stop and lava eruptions starts.

Please note that I am on slow internet connection (3G). So I am not going to post anything if the internet connection is really slow, as sometimes seems to happen. I am going to try and solve this issue by using my 3G phone and connect that way. At least I am going to try and see what happens.

Blog post updated at 03:20 UTC on the 15 October, 2011.

598 Replies to “Special report: Update 3 on El Hierro eruption in Canary Islands, Spain”

  1. The harmonic tremor is slightly growing again since a couple of hours. GPS deformation is also gradually climbing – so i think it is not over yet
    Why don’t we get the results of the water sample (at least i haven’t seen them)

  2. OT: Just so Iceland knows we have not lost interest (yes, I am superstitious) , more larger EQ there, including some north of Iceland.

    4.3 14 Oct 16:25:56 90.0 102.2 km NNE of Kolbeinsey
    3.3 14 Oct 16:26:07 87.2 42.4 km ENE of Kolbeinsey
    3.2 14 Oct 03:44:44 90.1 7.9 km NNW of Lokatindur
    3.1 14 Oct 05:07:23 51.5 74.0 km NNE of Kolbeinsey
    2.9 14 Oct 04:31:23 82.8 17.6 km WSW of Geirfugladrangur
    2.5 14 Oct 02:54:29 90.0 9.3 km NNW of Lokatindur

    link: http://en.vedur.is/

    And just so Katla does not feel neglected she has had a couple of tremors between 2 and 3:

    Friday
    14.10.2011 13:50:55 63.589 -19.126 1.9 km 2.3 99.0 1.7 km NW of Hábunga
    Friday
    14.10.2011 10:24:33 63.607 -19.123 1.2 km 2.2 99.0 3.2 km NNW of Hábunga

    link: http://en.vedur.is/earthquakes-and-volcanism/earthquakes/myrdalsjokull/#view=table

  3. I read somewhere that part of El Hierro was the remains of the caldera of a much larger volcano, El Golfo. Does this mean that the EQs occuring to the north & west of Frontera have more significance e.g. relate to an old vent or conduit of El Golfo?

      1. Note fig3 – best info I’ve seen on sub-sea contours – note ridge south of Restinga, site of current action.

  5. http://www.tumbit.com/news/articles/3942-next-eruption-on-el-hierro-hours-away.html

    “According to the Centro Superior de Investigaciones Científicas (CSIC) the next eruption could occur on land. The question now is where the next activity will be and when

    Professor Ramon Ortiz from the Center for Scientific Research (CSIC) commented yesterday that the only thing that can be said about the situation is that it will result in one of three things: the fissure which the magma will escape from will move south, to deeperwaters; that fissures will open further inland and twoards the coast of La Restinga; that new fissures could open up on the Island itself. “

  6. He’s left out eruptions that could cause cinder cones, of which there are many on the island. Any idea as to why he would do this?

    1. He hasn’t. A fissure eruption on the island would result in cinder cones. 🙂

  7. Earthquake focal mechanisms are calculated for large quakes so that an idea of the faulting mechanism can be determined. These are represented by “beach ball” and serve to illustrate the forces at work in the quake mechanism. The “first motions” of the waveforms at the individual seismograph stations are used in this calculation, and the more stations you have, the better the focal mechanism determination. Hence the tendency of large quakes to have the calculation done on them since more stations will be able to see it.

    Smaller quakes, such as those in and around El Hierro aren’t large enough for a proper focal mechanism to be run on them.

    In standard data processing, the exact location of a quake can not be determined. Sure, we see what appear to be high precision latitude/longitude/depth information, but this is actually very mis-leading. Unless you can dig down to the fault face, take it apart and actually look to see how long and along what axis it fractured on, you are limited to the data that you can glean from seismographs. For this reason, on technical reports of earthquakes you see information about the shape and size of the amount of error in the position data. This is the error ellipse.

    An ellipse, if you remember, has a semi-major axis, and a semi-minor axis. These are the long and the short dimensions of the ellipse. In earthquake reports, the azimuth of the semi-major axis is used to communicate the orientation of the error ellipse. In other words, which way the long axis is pointing.

    The actual dynamics of what goes into this error calculation has a lot to do with where the quake was at in relation to the seismo stations, the resolution of the stations time base, or how accurately they determine time. This affects the “picks” that are made on the waveform (automatic or manual) and sets that particular waveform in time with relation to the waveforms from other stations.

    Now that’s how and what an error ellipse is officially for.

    Now… the thought exercise.

    When a fracture occurs, it will happen along a plane. The energy will travel away from the break point in all directions, some energy will be compression, some will be extensional.

    My thought is that the localization of the quake will be poorest along the length of the break. If that is the case, then with all things being equal, the long axis of the error ellipse should be pretty close the axis of the break.

    If that is the case, we should be able to make some leap in logic to come up with a hint of the fracture orientations in El Hierro.

    REMEMBER, THIS IS NOT HOW THIS DATA IS SUPPOSED TO BE USED.

    So.. here are the azimuth errors for the El Hierro quakes.

    http://i56.tinypic.com/r0b0p4.png

    And odd thing stands out when you look at this in this fashion. If the error ellipses were just dominated by their spatial orientation with the seismo stations, you should see a pattern related to where they are with respect to the stations. To me, that doesn’t
    seem to be the only thing going on. It appears that the orientation of the error ellipses seem to be affected by what stage the quakes in the swarm were at.

    Enjoy the plot… and remember that there is no scientific basis for my idea.

    1. Should read “So.. here are the azimuth of the error ellipses for the El Hierro quakes.”

      2. They do show up. It is not clear. But it is the earthquake swarm at -18.05 to -18 and 27.65 and 27.70. In that box exactly.

        I believe that this is magma that has collected and might erupt at any time. If it doesn’t get stuck there. But I find that outcome unlikely.

      4. Great reasoning and great plot.
        It looks like there were two pathways formed through which magma is rising two fold and collecting in the caldera.
        Wish you are wrong…

    3. Here is a picture of the cummulative quakes from AVCAN (copyright belongs to AVCAN & Google):

      http://s1193.photobucket.com/albums/aa359/KarenAZ1/El%20Hierro/?action=view&current=El_Hierro_cum_131011_2.jpg

      While I was watching the animation of the EQs they started on the summit of the central peak of El Hierro then moved to a prolonged tight focus to the west of Frontera, followed by shallower quakes on the island then deeper quakes in the south of the island & the sea, with the shallow ones at La Restinga happening right at the end.

      From memory (which could be faulty) I think that the shallow quakes you are looking for could be on the east of the cluster of quakes towards the summit. I’ll trawl through my screen shots to see if I can locate them more precisely (quicker than watching the animation again).

    4. Very interesting idea to use the error elipses in this way.
      As far as I know you are the first to do this.
      I think you should write it up in a paper since it has great merrit and is usefull in other fields to.

  9. Close to home
    Mt. Rainier tremors,, 3.4 ,depth 8 followed 1 hr later by a 2.9 ,depth 0.9 (USGS)

  10. Thanks, Lurking:
    That’s where Jón suspects a new vent could open – a magma pocket.

    1. Almost exactly the region where the last quake occurred. A 2.7 mag, only at a depth of 16 km.

  12. Well, this one needs a sanity check.

    First of all, stations HI-01, HI-02, HI-03 and FRON were located via a graphical overlay on Google since I could not (and still can’t) locate them in any official document. The same applies to the other stations that were used for reference.

    Second, the horizontal displacements were determined via importing the various graphics into Dplot and locking the plot boundary to the background image and measuring the displacement from yesterdays values compared to the most recent value.

    Three, a surface plot was made using the derived coordinates and the measured displacements. This plot was then re-gridded (quadratic) at 255 points for the plot area. This image was then exported to a graphic and then moved to Google Earth as an overlay.

    The Latitude and Longitude was then matched as close as possible and then screen capped.

    There is a lot of room for error, so take this image with a grain of salt… possibly even the whole salt lick.

    It shows horizontal displacement with relation to station FRON.

    Something that would be nice, is to have a clue about where station HI-04 is at. I think that would add a great deal to the image.

    Ruminate at your leisure.

    http://i51.tinypic.com/4ugqid.png

    1. Does this fit with the known fissure (crack) running under El Hierro ? Don’t think so.

      1. Actually, it fits quite well.

        The brunt of activity pre mid September was along that N/S axis.

        The violet color is horizontal displacement away from FRON which is to the east of that area, and the redish color is further west of that, which indicates motion towards FRON.

        This tends to indicate a possible elevation of the terrain between those two zones.

        Keep in mind that this is just the motion of about one day… it’s not very large and the displacement is in millimeters.

        And, to answer another question somewhere along this thread… this is a plot of motion towards or away from FRON.

        I was about half way through extracting the N/S and E/W components, and then realized that it really didn’t matter since pure horizontal motion related to FRON would do just fine.

        If I had HI-04’s location it would probably make the plot much clearer. (as would the real data, but researchers are pretty possessive of that)

    2. It is very interesting. Not surprising given the focus of EQs early on in the series from July.

      Could you explain the direction of displacement? You either have:

      a) some evidence of rifting on part of the fault; &,
      b) some evidence of the areas moving closer together (caused by magma moving away from that area to south? or folding?)

      Can you do the same on on vertical displacement?

      1. I wish I could. The only data in the graphs is the change in distance between the various stations and FRON.

        I did find some raw GPS data, but it’s for the stations spread across the canaries and doesn’t easily lend it self to interpretation by non-specialists such as me. (orbital errors, correction signals, all in RINEX format.)

        The only GPS data that I could find that had elevation data was from a set of stations operated by a Japanese researcher, and that data doesn’t have a consistent update rate. The one plot that I did that used the vertical displacement came from his set, but I had to interpolate and run trend lines to get an idea of where the stations were at on the same dates.

        A kludge at best.

  13. @Lurking, I can’t find that amount of quakes in the IGN catalog with that depths betwen August and September. Have you used the earthquakes which have an unknown depth?? I think they could be given a depth of ~0 km or so, but they actually don’t have a depth known…

    1. I leave out the unknown depths.

      My logic is that if the quakes are vague enough to not have a depth, they can’t add very much usable info in a 3D/4D plot.

    1. Don´t understand how they dare to go on…that was a big one. Is it possible that they could kickstart an eruption or at least wake the volcano up?

      1. I think last week Carl said that it could be that the earthquakes happened without water being injected. Or it was discussed because people were thinking nobody works on saturdays. Does anyone have any information if this new swarm is a reaction to works or if it is happening on its own?

      8. The most recent is at Hveragerði some way away from the pumping site, if its location is fixed correctly. That should be cause for concern.

      9. This last quake appears to have been removed from the SIL station. Perhaps they are reviewing it and it will appear again later? Just seems odd when quality scores have not been adjusted or confirmed as yet to only take this one out.

    1. Enrique (AVCAN) points out that the seismicity trend along the NNW-SSE plane seems to be moving further westwards than the axis of previous days… Further indicating the possibility of what appears to be the network of faults and fractures in the Tanganasoga volcano complex area.

    1. They say this in your link…Undanfarnar vikur hefur verið niðurrennsli í borholur á svæðinu.

      Roughly translated, “Last week have water been ejected down in the borehole…” I am guessing my way through the icelandic language, I speak a few sentences if need be.

      1. I am fluent in Icelandic having lived there for 6 years.

        They don’t talk about people injured in the article, but shocked by the quakes. And that they felt them well in Reykjavík and Mosfellsbaer, about 25 km from the site.

    1. Nah, let the crazy scientists give it a go!

      And also, I didn’t get your FB-friend requests! You must have added one of my namesakes!

    2. It is suicidal, especially as they appear to have continued after producing two large EQs without stopping to check the impact. Maybe their monitoring equipment needs an upgrade.

      There have been several EQs >3 on the Mid Atlantic ridge to the north recently and one at Askja. The large EQs may have been caused by the drilling, they may have been caused by tectonic plate movement or they may have been caused by magma movement. But who is going to know now?

  22. This is interesting: the Canaries’ volcanics are sitting on a layer of Jurassic and Cretaceous sediments lying on top of the oceanic crust.
    http://www3.imperial.ac.uk/earthscienceandengineering/research/geophysics/earthstructure/canaryislands
    The layer is around 3km thick, and its lower bound is at approx. 8km depth.

    Here’s the question . Is is coincidental the the cutoff in EQ depth occurs at that depth, with very few of the 8000 ocurring shallower: lower panel here:
    http://www.ign.es/ign/resources/volcanologia/html/eventosHierro.html
    What seismic signals should we expect from magma penetrating sedimentary rock?

    1. If there was a volcanic ash cloud over Europe (from either Iceland or the Canaries) at the time of the Olympics, you could use boats or Eurostar but you had probably better get the booking in now because there would be chaos later.

      But if travel was really difficult, the Olympic Committee should consider delaying the games to be fair to the participants.

      1. Funny, I had to drive from Stockholm to London during Ekja last year, because my flight was canceled. Only took 22 hours overnight including ferry ride and lots of red bull…

  25. From AVCAN facebook site… Madrid Meteo Ciencia satellite photo of submarine ‘eruption’ site
    http://www.rapideye.de/images/flood/el_hierro_20111013_2.jpg

    Why do I put eruption in ‘inverted’ commas? See opinion of geologist José Luis Barrera regarding uncertainty about whether only gases, not lava, have been released so far, and the plume is only disturbed seafloor sediments…
    http://www.canarias7.es/articulo.cfm?id=233565

    The Madrid Meteo Ciencia photo shows an oval shaped plume at the surface (which can be clearly seen in recent Guardia Civil photos), orginating from two clusters of activity (ENE of oval). The elongated smear SW of the oval is current dispersion of plume material over last few days.

    Does anyone know of any (publically available) sampling and analysis of the plume material?

      1. Wow Andy – thats a great picture – Now, 3 days after Carl’s analysis they start discussing the subject. Tell them to hire Carl 🙂

        In another article yesterday in one of the local newspapers somebody told the journalist the the big plume who is coming closer to the coast right now is because of the currents? Looking into the German satellite picture, it seems to come from 2 distant vents (far out in the sea) and then picked up by the current to become greater . Whats your opinion about this ?

      2. From recent pictures (e.g. http://tenerife.todogeologia.com/download/file.php?id=400&mode=view) it looks like the sediment plume is spreading in all directions, including towards the coast, which is normal and does not necessarily indicate an increase in activity/disturbance at the seabed (something confirmed by no change in spectral/seismo charts).

        In the 500-750m deep water column above the vents (yes, 2 clusters of multiple fumeroles looks probable from the photo) the water currents will move in different directions/rates at different depths. Therefore, the long ‘streamer’ of plume material stretching SW into the deep ocean probably reflects a current at 20-200m depth. Whereas the surface current (0-20m) may be more tidal (moving back and forth) and wind affected, hence the disk-like shape we see in photos.

        By the way, the sea floor bathymetry maps show many cone like structures on the ‘Southern Ridge’ offshore rift zone that stretches 40km south of El Pinar/Punta de la Restinga promontory. It is not surprising that volcanic plume activity should manifest itself along the region of this ridge.

        It also looks probable that the plume is mainly meso-pelagic sediment (mix of clay minerals and biogenic siliceous and carbonaceous muds) that has been remobilised by venting of hot volcanic gases (there is strong smell of sulphur on land) and steam from seawater & submarine groundwater being rapidly heated. The vents – fumeroles – are likely to be many small fissures and tubules rather than big ‘open mouth’ type vents. (Kind of, fill your jacuzzi with sand and gravel and silt and turn on the bubbles! The bubles come up all over the place, and send plumes of silt to the surface. The heavy stuff stays down there (we hope!)

        What we ALL wait for now is confirmation (or not) that there is new igneous material (pillow lavas) erupting at the sea floor.

        The research ship Professor Ignacio Lozano of the Instituto Canario de Ciencias Marinas (http://www.iccm.rcanaria.es/) is in the plume area right now (Sat 15 Oct) taking samples (but has no ROV).
        https://picasaweb.google.com/113722149580960588275/FotosSacadasDesdeElBuqueProfesorIgnacioLozanoDelInstitutoCanarioDeCiencias?feat=flashalbum#5663681097411182930

      3. To reach the submarine fumaroles gasses have to traverse about 3km of Jurassic sedimentary rock – see URL in my post above . Possibly the higher temperature needed to produce partial melting of that 2miles of sedimenary rock has prevented magem reaching those vents, but not gasses?

  26. Giggle translation of the article on ruv.is concerning this mornings earthquake:

    “”””””””
    Much has been earthquakes in the Hengill area in the morning. The two largest earthquakes were a size 4 and the first rider over at 9:03 and the second at 9:46.
    The largest earthquakes have been found throughout the metropolitan area, operated there, the Akranes Hell and beyond.

    A total of 75 earthquakes felt since midnight and most of them have been on or after nine o’clock. According to the IMO earthquakes cycle is now similar to that of the earthquake cycle on the paths in September. This was Hellisheidarvrikjun. In recent weeks there has been a drainage wells in the area.

    “I’ve never had this before, but I woke up to this,” said Robert Gudmundsson, who claims to have been concerned about the seismic function. He says he woke up with a shake of his bed and be very alarmed. It was the second major quake. Residents operated there and Mosfellsbær have felt the quake and many of them have been broken, according to interviews with the newsroom. Residents of Lindahverfi in Reykjavik also found for the earthquake which hit shortly before ten. A man who contacted the newsroom said he felt the earthquake was coming and that he would be quite powerful when it struck.

    Overview of the earthquake can be found on the service. There is, however, the Preliminary figures, and two large earthquakes, for example, listed as 3.8 and 3.7 in size than the experts went over the figures showed that there were 4 in size.
    “””””””

    1. Thanks, i translate it to german for me. But my english is not good enough to correct some mistakes.

    2. Everybody in Reykjavik, Mosfellsbær and Hveragerði felt the latter quake.

  27. Edilia & Espeleo over at TodoGeologia.com – TENERIFE forum have tried to summarise expert opinions on situation regarding the submarine ‘eruption’ near La Restinga, El Hierro (Posted: October 15, 2011 13.08 & 13:15)
    http://http://tenerife.todogeologia.com/viewtopic.php?f=1&t=1782&start=855

    Google translate is not very clear (in English), and I don’t want to misrepresent anyone, so you will have to translate it for yourself…

    However, my interpretation is that the experts generally think it is mainly gases and either no or very little lava, so far. The plume is remobilised sediment, and other ‘eruptions’ are likely along the fissure, closer to the island, in coming days.

    Anyone with Spanish who can be more accurate? Please do let us know?

  28. Andy:
    Couldn’t find the article you mentioned , but I suppose that this idea has been suggested over this blog. In the very beginning, the clear water “green spots” looked rather with discoloration caused by gases and no further gunk associated to it.
    Now the plume became quite clear, and that’s also Jón opinion. There was indeed an eruption, and no doubt other eruptions are likely (newer vents).

  29. Re Hengil swarm
    It is worrying to say the least. But I have no constructive comments to make until it is determined whether drilling and or fracking has occurred in the last 24 hours. I hope really that that explains the latest swarm and larger quakes. If no human activity has occurred then these seismic events are of concern.

    El Hierro is still a mystery. I like mysteries and I follow the plot with the help of Lurking’s illustrative postings. They certainly give food for thought.
    Again my thoughts are with the residents who must be feeling frustrated at the lack of knowledge and clear information. But this is all part of the long and difficult studies which may one day giverise more accurate predictions.

    To those who seem to think the Mad Scientists that are watching El Hierro are simply “enjoying” the Happenings.
    Very far from it. Most Scientists, especially Vulcanologists are only too aware of the destruction and death that volcanoes can bring.
    They are these days in a better position to discuss and “see” what is happening beneath the ground. This is thanks to the advancement of technologies that were only dreamed of 30 years ago.
    If scientists seem overly excited, it is because at last they can make more positive steps towards predicting the behaviour of volcanoes or earthquakes and so are stepping ever closer to minimising the havoc they can cause and most importantly save lives.
    So please understand , the discussions here and on other science based blogs are predominantly and genuinely science in action, with a common aim to find ways to accurately make predictions based on accurate data to minimise seismic and volcanic risk.
    I emphasise that at the moment nobody can accurately predict the start of an eruption (anywhere in the world, not just at El Hierro), there can only be suggestions or informed “Guesstamates”.

      2. They are insane… totaly crapola behorkedly insane.
        A mag 6 right next to the magm-reservoir of Hengill? That will be the first manmade eruption. They could equaly well set off a 1 megaton nuclear device in the magma-reservoir.
        I guess Irpsit won’t have a home to come home to.

      3. Tranlation from mbl.is:

        Two earthquakes, which happened at Hellisheidarvirkjun at 9:03 and 9:46 in the morning, were both of size 4, but were felt to a varying degree depending on the fisure they were on, says Gunnar B. Gudmundsson, geologist at the Icelandic Meteorological Office.

        “These are human generated earthquakes, and there have been a few cycles since September, but those are perhaps the largest earthquakes to date,” says Gunnar. He says that Reykjavik Energy consistently lets water flow down into four, five holes at Heillisheiðarvirkjun which they are obliged to do under the operating license of the plant.

        “By letting the water flow, they change somewhat the tension level in the vicinity. The rock is all cracked and the water goes into the cracks and reduces the so-called horizontal stress, and then there is always tension in the area due to tectonics and other, and then this can snap” says Gunnar.

        NEA is currently working on a study to shed light on the nature of earthquakes and assess the effects the minor quakes have on the stress condition in strata, and possible changes in seismicity in the long term.

        On the RE website it says among other things, that the residents of surrounding communities wonder whether artificial quakes pose an increased risk, and whether the situation will persist.

        “If this activity continues with this kind of major earthquakes then I think it’s not going to continue for long” says Gunnar. “We know that to the south of the area larger earthquakes can occur of up to 5-6 on the Ricther scale,” he says. The question is whether the manmade earthquakes increase the activity in the region and could cause larger earthquakes.

        Result of Reykjavik Energy study is to be available in the coming days.

  30. Andy:
    In this article:
    http://www.canarias7.es/articulo.cfm?id=233565
    Barrera dismisses that lava is rising to the surface and that the water colors seen closer to the island is due to gases at shallower depths.
    He only says he cannot assure that an eruption took place at deeper waters, simply because no one has seen the lava yet.
    We all know that the only way to find out is to dive in the depths to see the pillow lava formations.

    1. just saw a tweet that said an eruption is occurring and there is visible lava.

      The tweet came from a search. The person that tweeted it is: @ Kivicito
      Kevin Felipe Cabrera

      Do a search for: #ElHierro

  32. A new eruption started 30 min ago on El Hierro, and this time it’s visible above sea. People who were in La Restinga to get things from their homes are now being evacuated again. They say a new vent has opened 2 miles from the coast and magmatic material is visible. It is no longer allowed to fly over the area.
    http://www.canarias7.es/articulo.cfm?id=233604

      1. Even if the eruption occurs in shallower waters, magma will only be visible in the form of ashes and there will be a great phreatomagmatic explosion, which is not the case.
        Another possibility of “visible magma” is a fissure opening in dry land, and then, what will be seen, is a Fimmvörduháls or Piton de La Fournaise kind of effusive eruption.

    3. Yay Google…

      “ordered the bailout of the neighbors who had been allowed to go back to La Restinga, El Hierro, to take personal belongings to a new eruption within walking distance from the coast, officials said.”

      For those that may miss the nuance. That mangation indicates that the residents are being allowed to take their belongings to the eruption.

      Must be some sacrificial thing. “Here, take our stuff, could you stop now?”

  33. Luis, Mirri:
    Lava is not visible according to the article, only the spot, as the other two.
    Authorities are taking precautions for the case of another vent opening nearer to the island.
    This one is still at 600 m depth, so lava will just stay at the bottom.
    No alarm yet.

    1. Furthermore, I don’t see any significant increase in tremor, as the article says.

  34. Mirri & Luisport… See my reply to Armand Vervaeck (October 15, 2011 at 12:03)

  35. Thanks Renato… I would have expected everyone with an ROV to be racing to be first at El Hierro! Where’s that dude who found the Titanic??????

    1. Perfecto, Andy.
      Until we see the basalt in the form of pillow lava no one can assure there was an effusive event underwater. Albeit, it is likely there was.
      And the fact that the currents are showing misleading spots of new vents is also very plausible.

      1. Google translate of latest AVCAN news…

        “At 1315 hours it has ordered the bailout of the neighbors who had been allowed to go back to La Restinga, El Hierro, to take personal belongings to a new eruption within walking distance from the coast, officials said.

        The tremor has intensified and the rash is visible from shore.

        Magmatic material has left open by a fissure two miles from the coast. Have been banned over the area and the research vessel sent to the scene has been ordered to leave urgently.

        Photo of the public, the spot yesterday when I touch the shore.”
        http://fotos.subefotos.com/dafcc42193d1720310363088b3b51654o.jpg

        Everything I write earlier today… Time for a review! If that is a new plume disk (and not just a change in current conditions) then it does look like activity (even if only gases) is moving much closer towards the island. Shame that the research vessel is ordered to leave (better to be safe than sorry of course, but most oceanographers and geologists I know would say “keep us here, please” this is too important to miss!)

      2. Some official on RTVC just said there was no confirmation on visibility of the eruption. It appears to be at 2 miles off the coast. I think the rumours is because some people have said (twitter) they saw the ‘clouds’ change color, more to a dark greyish color…

      1. The ROV that checked the titanic was the same Hercules which can be watched on nautiluslive.org this very moment. And they are on the Gettysburg Seamount in portugese waters.

  36. I’m not convinced yet that lava is upwelling in the sea south of El Hierro. Even what looked like an eruption on oktober 12th at ~ 14:20 cold be just a bigger breakthrough of the seafloor and more violent release of gases. And the greyish colour of the last occurred stain on the surface could be formed by clay and debris from the seabottom.

    This morning I was thinking about the three possibilities being considered at the moment on El Hierro
    (source: http://canariasimporta.blogspot.com/p/al-minuto-sismos-el-hierro.html, 12.10.2011):

    “Regarding the evolution of the eruptive process, Ramon Ortiz, head of CSIC scientists explained that currently are handled three possibilities: that exploded off the coast, in the interior of the island or in deep water.”
    Original Spanish text:
    “Respecto a la evolución del proceso eruptivo, Ramón Ortiz, responsable de los científicos del CSIC, explicó que, en este momento, se manejan tres posibilidades: que explosione en la costa, en el interior de la isla o en aguas profundas.”

    But – could there be a fourth, more peaceful possibility? I wonder if the only thing that will happen at all is a release of gases for some time at different locations, and the forming of new cones maybe. Look at the map how many cones (read somewhere: about 500) already have been formed! Yet little to be seen of former eruptions. No caldera.

    1. Sissel:
      There is an eruption underway. It is a fissure eruption. It could stretch further North or South, into deeper waters. This last possibility is the more “peaceful” one.
      Now, if magma comes in contact with shallow waters, there will be an explosion, therefore, the nearby region must be evacuated.
      If the fissure proceeds further North, into the land, new cones will be formed and we will have nice fireworks to contemplate, a long as no one stays on its path.

  37. IMPORTANT UPDATE 12:57 UTC : A NEW eruption is currently going on at 2 nautical miles from La Restinga. This news has been brought by local newspaper Diario de Aviso. We have no pictures of the new eruption yet – More information will be available here soon. This new event cannot be seen on the seismogram like in earlier events.
    At 13:15 local time an urgent order has been given by the authorities to immediately evacuate La Restinga. Some local people have been allowed to pick up personal belongings.
    – The new eruption is said to occur at a depth of 600 meter and approx. 2.5 km from the coast.
    – Authorities are claiming this time that the eruption taking place is a Magma eruption.
    – Helicopters and airplanes have been ordered to NOT overfly the new eruption spot and the “Profesor Ignacio Lozano” oceanographic ship has been ordered to IMMEDIATELY leave the sampling area.

    http://earthquake-report.com/2011/09/25/el-hierro-canary-islands-spain-volcanic-risk-alert-increased-to-yellow/

    1. teideano teideano on twitter:
      #elhierro estoy en el puerto de La Restinga y no veo absolutamente nada anomalo….

      = I am in the port of La Restinga and I don’t see nothing anomalous… 8 min. ago

    2. Luis: Don’t run too fast to the news!
      If there is an eruption, magma is always involved.
      Under 200 m magma won’t be seen, but it is there, spewing the gases responsible for water discoloration.

      1. Renato don’t Storm me, i only post local media news! They can be exagerated, but that’s why you guy’s are here! To put whater in the fire…

      2. Yes… when they can prove or show any evidence to supprot their statements. To spread news which can only cause confusion and panic to people is very, very, wrong.

      3. I don’t spread news! I post it, so you can comment it! It’s my only objective!

  38. Jesus Alvarez More details: “the appearance on the surface of the sea of a mixture of gases and magma, known as pyroclastic flow, has forced the closing of the accesses to the port of La Restinga and the prohibition of the flight of aircraft and helicopters in the area.”

    Sources of the Pevolca, the special plan of civil protection to the volcanic risk, reported EfE Oceanographic ship that was in the area to collect water samples where the eruption has been fisural has abandoned the area.

    In the port of La Restinga, where its 600 inhabitants have been evicted since last Tuesday, it was also now a small group of neighbors who were withdrawing their belongings.

    The pyroclastic flow is a mixture of gases and solids ejected in eruptions of volcanoes that forms the strained pyroclastic, so-called “burning clouds”.

    “This compound occurs when lava with high content of dissolved gases (e.g. oxides, sulfides, or water vapor) is cooled and decompressed to surface during a volcanic eruption.” http://www.RTVE.es/Noticias/20111015/volcano-iron-eNTRA-erupcion-eject-lava-dos-millas – coast/468537.sHTML

    1. There will be no pyroclastic flow from this eruption, because this is lava with low viscosity and not of the explosive kind. We would see pumice rafts floating on the surface if it were.
      Take the example of Hawaii!
      No pyroclastic flows!!!!!!

    2. They also moved the guarded access/road block that is on the road to La restinga back about one km. They would not do that if here was no danger.

      There will be a press conference in about an hour by PEVOLCA that will give more detail about the findings of the crew on the investigation vessel.

      Keep in mind that the ocean floor dives down pretty fast around El Hierro. 500 metres is pretty close to the shore.

      1. NO PYROCLASTIC FLOWS!!!!!!
        The media is going hysterical, I only wished you guys keep cool and matter of fact about this.
        Of course there might be some danger if we have a phreatomagmatic (Surtsey type) eruption near the harbour.
        So, people must getaway from there, and everyone will be safe.
        See Andy’s comment below.

    3. A bit about pyroclastic flow.

      There will be NO pyrocalstic flow what so ever until one of two things occur.

      1) Dome collapse and the material surges down the side of the mountain.

      or

      2) And eruptive column (up into the atmosphere) looses it’s energy and collapses back upon itself and then surges down the side of the mountain and across the terrain.

      Having said that, where the eruption is at, doesn’t have a dome on top of a mountain, so that rules out #1. If #2 is at play, you won’t need a helicopter or ship to see the column. It would be glaringly evident that something drastically bad had happened. There would be no question at all about what is going on.

    4. sounds more like an excellent post at the exintction protocoll…sounding alarm bells when there are none to show for it.

  40. Earthquakes today, are rising gradually towards the surface: 1105638 15/10/2011 09:39:43 27.6708 -18.0316 15 2.5 4 SW PINAR.IHI 1105629 15/10/2011 06:59:33 27.7273 -18.0821 16 FRONTERA.IHI 1.8 4 SW 1105626 15/10/2011 04:50:23 27.7175 -18.0767 15 1.5 4 SW direction FRONTERA.IHI 1105621 15/10/2011 03:52:21 27.6668 -18.0559 16 2.7 4 SW PINAR.IHI

    1. I don’t see them getting shallower…
      Por favor, Luis, verifique suas fontes e não incorra no erro de publicar notícias sensacionalistas, sem comprovação.
      Abraços

  42. I think we need to be careful now…

    There is a lot of bull s#!t flying around the Spanish media right now about submarine pyroclastic flows (!) and eruptions endangering ships and helicopters… The blogoshpere is already going into ‘end of the world’ mode.

    The only things for certain are: no eruption is visible from the land. The plume colour is now grey-brown and closer to shore than yesterday (which may indicate sediments from shallower depths being mobilised by gases/steam as before). And there was another moderate EQ recently (there are a number of these each day).

    1. Especially as the last EQ reported on IGN was between 9am & 10am this morning. But IGN may be slow to update today.

    2. Well said Andy. Gathering facts, when they are proven constructing ideas and thinking on this solid base.

    3. Anything that happens at depth in the ocean is unlikely to be an danger to ships. It can sad that helicopters are safe from anything that happens at any depth in the ocean. All the dommers on the blog sphere love this type of news. Since they already do not care about the facts.

      So the Spanish media is just making up bullshit news now.

      1. It’s not my case! I only report the medis news… it’s impossible for me to see if it’s true or not!

      2. It’s OK. We know… Just that there are so many people out there (not you!) who are willing to spread panic for no good reason — Some even get paid for it ; )

      3. I thing that if someone want to spread panik news will not post here, or he will be stupid. This is a serious blog, not a GLP!

      4. I concur with Andy Scollick (below)

        Just make sure that you note in your updates who is making the statement or where the source is. If it’s an official being quoted that lends more credence to it, especially if it’s a geophysicist.

        If it’s a reporter prattling on, it probably isn’t worth the trouble unless it’s in the category of an eyewitness seeing a column soaring skyward… that would be newsworthy. Also quite disturbing.

      5. Okay, “above.” The different ways that these blogs handle follow ups can be a pain.

    4. A calmer response from El Mundo:

      http://www.elmundo.es/elmundo/2011/10/15/espana/1318684618.html

      The appearance on the surface of the sea, 2.5 miles offshore gas and magma, known as pyroclastic flows, has confirmed the existence of an underwater volcano off the port forcing the closure of the entrances to the port of La Restinga and ban on helicopter flights and aircraft in the area. Has also increased the security perimeter in the area, as reported by Michel Martin .

      The president of the Cabildo Hierro, Alpidio Armas, explained that the material is due to a magmatic eruption underwater to 900 meters deep.

      Pevolca sources, the special civil protection plan to the volcanic risk, have reported that the oceanographic ship was in the area collecting samples of water where there was fissure eruption has left the area .

      In the port of La Restinga, which have been evicted from its 600 inhabitants since last Tuesday, so today was a small group of neighbors who were removing their belongings. Hierro President says no risk to the population .

      The pyroclastic flow is a mixture of gases and solids ejected during the eruptions of volcanoes that form the pyroclastic lava flows , also called “burning clouds”.

      This compound is produced when lava with high content of dissolved gases (eg dioxides, sulfur or water vapor) is cooled and decompressed when they reach the surface during a volcanic eruption.

      1. Karen: What they refer to is “piroclastos fumeantes” that doesn’t mean pyroclastic flows. Pyroclasts are any magmatic material expelled from a volcano. Probably a phreatomagmatic eruption has started, spewing ash and because of the explosion some “lava bombs” which are nothing but “piroclastos fumeantes” – smoking pyroclasts.
        But given the witnesses saying that they cannot see any plume, I suppose the eruption, if there is any, is still in deeper waters.

      2. The lava at El Hierro has poor silica content, with little or no gases trapped in bubbles, so it won’t be able to produce the dangerous pyroclastic flows we saw at Merapi.

    5. Actually you can have a submarine pyroclastic flow.
      Of course it would be different than it is subaerial version, but on general the same principles should aply.
      In theory you can have superheated ash-sludge making a mudslide if the bottom drops off steaply as it does here.
      But, it would not cause any harm what so ever.

      Luisport; Please do not stop to translate the news from the spannish News. It is not your fault that they are alarmist and erroneous. I do like it, because now and then they print a usefull tidbit. Sorry Renato, this time I do not agree with you.

      1. Thank’s Carl… and i thought that you don’t like my posts… Renato was desperatly trying to put this out of panik mode! But i was not understanding that spanish expression they use as piroclastos humeantes… and google don’t help me!!! Sorry Renato for the confusion. Let’s go on! ;-D

      2. I do not always agree with you. But I always believe that people should be allowed to write what they wish.
        I do not have any problem with what you are writing Luisport, but I do have a problem with a few people that have been ranting about “end of the world thingies” the last few days. But to my knowledge you have not done that.

    1. I read that some people near the coast cannot spot any eruption from where they are. Too much hype over this.

  44. Many of us come at this from an Icelandic volcano perspective. But Hierro is very different -its not like an Icelandic volvano at all. The Canaries sit on a 3km-thick layer of Jurassic sedimentary rock itself sitting on the oceanic crust:
    http://www3.imperial.ac.uk/earthscienceandengineering/research/geophysics/earthstructure/canaryislands
    You can see on the schematic that the base of this sedimenatary layer is at 8km depth.This corresponds to the shallowest EQs seen since July:
    http://www.ign.es/ign/resources/volcanologia/html/eventosHierro.html
    So it seesm yo me that it is reasonable to suppose that the 2mikle thick layer of sedimentary rock is delayinh upward porogation of magma. I
    Is this reasonable to suppose?
    If so can that sedimentary rock be limiting the movement of magma below the site of the submarine activity such that gases escape but not much in the way of magma?

    1. Peter:
      That is possible, indeed, and we won’t know for sure until a submarine checks the spot or a subaerial eruption takes place.
      IMHO I think magma has already been released from the first event, but it’s merely a guess.

    2. I think that what we are seeing is that the magma has very little resistance in sedimentary rock. It’s about the difference in driving a tent stake into soil as opposed to rock. Yeah, siltstone/sandstone/shale is a rock, but it’s not as strong as gabro and the magma would have very little resistance there… so, less quakes.

      1. The sedimentary rocks appear to be partly limestone – so would we expect more CO2 from that when heated, to contribute to presenr activity?

        Did not know limestone lay under any Icelandic volcano.

        So the passage of magma up through seismically silent sedimentary rock layer could have been happening ever since the swarm of EQs topped out at 8km deep. Perhaps the EQs will reappear at 5km deep once the magma has got through the sedimentary layers?

      2. I think the CO2 will be there either way. Yeah, the limestone could contribute to it.

        Limestone in Iceland? I don’t think so. I could be wrong. As for limestone at El Hierro, not sure. Generally it comes from reefs and phytoplankton residue that has layered down over millions of years so I guess that’s possible.

        As for the silent non quaking layer… you are probably correct.

      4. @Lurking
        Could it be that the N-S declination of the upper bound to your plot of the EQ swarm is reporting a slope in the crust/sedimentary boundary?

      5. I don’t think so. That cant in the quake orientation was too steep to be easily explained with sediment. My gut feel is that it was following the likely lineation of the actual crust that was formed when this region was at the MAR millions of years ago. Plus they were too deep to be up in the sediment region.

    3. Most of Iceland is in fact on older crust, that is up to 65 million years old or older (from the studies that I have read and theorise this). But the top layer is younger and it age and is no older then 25 million years old.

      But there is not that much difference between Iceland and Canary Island. The only difference is that Iceland is on a rift zone. But both areas are on a hotspot.

      1. Jón, I am concerned about what people are saying at AVCAN threads, maybe you could say some words of reassurance, they trust you. They are fearing that pyroclastic flows will be reaching the coast, and so forth…

  45. @Lurking

    I just had a search around for the various seismographs you said you were missing, best I could find was this page http://wwww.01.ign.es/ign/resources/volcanologia/html/deformacion.html

    which looks like it might have the data at least in terms of a map with a scale, but my old machine couldn’t handle all the active page components so locked up before I got to click on the map – which might lead to actual coordinates.

    Hope it’s useful
    Edward 🙂

    1. Its handy, but it’s also the one I have been working with.

      I was able to get a rough, but close approximation of the main stations, but HI-04 isn’t on the map.

      1. tried again but it is not here either
        http://neic.usgs.gov/neis/station_book/H_BOOK.html

        but there is a FRON here http://www.isc.ac.uk/cgi-bin/stations?listn=F but it’s in Italy and not at Frontera, I guess IGN have just not registered these 🙁

        and it’s not here either (but I thought I’d post this link as it’s a csv and might save time in the future) http://www.google.co.uk/url?sa=t&source=web&cd=10&ved=0CFsQFjAJ&url=http%3A%2F%2Fwww.geo.lsa.umich.edu%2Fgeodisplay%2FHelicorder_Port%2Fstation_comma_list_asc.csv&rct=j&q=seismograph%20Frontera%20lat%20lon&ei=4KCZTpKAMYLA8QPz9ey6BQ&usg=AFQjCNEWSYS4iZFMw9rgzQ9MqJOzv8jOvA&cad=rja

  46. Does anyone know if any of the press confrences given are broadcast live on TV or Radio, and if so where?

  47. I think you forget that volcanoes in Canary Islands are capable to produce big explosive eruptions. It happens in a long time interval, but the historical studies says that is possible. At Least, in El Teide explosive eruptions have ocurred in the past

    1. Personally, I’m not saying that it won’t happen.

      But if it does happen, there will be no question about what has happened.

      1. At the moment we don’t know nohing about magma composition, gases, etc etc, so I think is impossible to say which kind of eruption could happen in an hypothetical subeareal eruption.
        We only could talk about probabilities.

      2. Guifre:
        Yes, if there is a caldera collapse or something of that size, then we would see an explosive eruption of the kind. But given the effusive nature of the hotspot magma and the characteristic fissure eruption we are currently seeing, the odds of a big such event are minimal.

  48. Update 15/10 – 14:15 UTC : Part of the emotion at El Hierro comes after the Guardia civil has closed a 2 km perimeter around the Tacaron cruce (we think this is the cross square where people have to choose among La Restinga and Tacaron). The cross Square point was the last couple of days a viewing point to see the Colored sea area.

    Update 15/10 – 13:55 UTC : Joke who is currently near the El Pinar press center at El Hierro just heard from a “to be trusted” journalists, that the news of the new eruption was based on ” volcanic material floating to the surface”. Journalist who were allowed to the viewing points came back stating “Nothing to see”.
    – People are getting really nervous on the island and rumors of More To Evacuate had to be declined fast to regain calm

    http://earthquake-report.com/2011/09/25/el-hierro-canary-islands-spain-volcanic-risk-alert-increased-to-yellow/

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